Sifu tends to commit around 30-45 minutes to each facet of the training:
Qigong & stretching (60-90 minutes)
Bagua (30-45 minutes)
Partner drills and wallbag (15 minutes)
Weapons drills & forms (30-45 minutes)
Tai chi empty hand forms (30-45 minutes)
Should you train this much? It depends on what you want. Do you want be Mozart or just to play a tune?
Ideally a green belt beginner should commit 30-60 minutes a day to training whilst a black belt student would be looking at 1-2 hours.
An instructor is another level entirely, with 3-5 hours solo practice a day. Reading/study, additional exercise (i.e. walking), constructive rest and teaching comes after.